US1959095A

US1959095A - Roll table

Info

Publication number: US1959095A
Application number: US554508A
Authority: US
Inventors: Etherington Harold; Moll Karl Hermann
Original assignee: AO Smith Corp
Current assignee: AO Smith Corp
Priority date: 1931-08-01
Filing date: 1931-08-01
Publication date: 1934-05-15
Anticipated expiration: 1951-05-15

Description

May 15, 1934. H. ETHERINGTON ET AL l 1,959,095

ROLL TABLE Filed Aug. 1. 1931 2 Sheets-Sheet l 1 N VENTOR Hqrold Ehelingfon Kar-z H. Mol! ATTORNEY.

FIL: h

May l5, 1934. H. ETHERINGTON ET AL 1,959,095

ROLL TABLE Filed Aug. l, 1931 2 Sheets-Sheet 2 56 l 29% 8 32 sa z5 54 48 3 5 lNvENToR:

' 40 Harold Ezheringfon BY Karl H, Moll ATTORNEY.

Patented May 15, 1934 UNITED STATES ROLL TABLE Harold Etherington and Karl Hermann Moll, Milwaukee, Wis., assgnors to A. O. Smith Corporation, Milwaukee, Wis., a corporation of New York Application August 1, 1931, Serial No. 554,508

4 Claims. (Cl. 80-44) The invention relates to machines for hot rolling metals and especially to roll tables which are used to receive and transport hot metal which is to be taken to a roll stand or which has been passed through the rolls.

In hot rolling metals it is commonly the practice to pass heated ingots and rolled metal over roll tables or ways which are open to the atmosphere and are comparatively cold. Large amounts of heat are lost from 'the time the metal leaves one set of rolls until it is given its next reducing pass. Among the greatest heat losses are the losses which result from radiation. The loss of heat by radiation and by contact of the metal with cold surfaces, such as the conveying rolls, is by no means uniform. This results in lack of uniformity in the ductility of diierent parts of the metal which is being rolled. The cooler portions of the metal subject the rolls to greater stresses than the hotter and more ductile portions of metal.

The maximum reduction which can be made by one pass through a given set of rolls must be regulated by the amount of reduction which can be given to the coolest portion of the metal which is to be rolled. In rolling smaller sizes, in which the heat capacity of the article is small as oompared to the radiating surface exposed, the greatest cooling of the metal to be rolled is present. In the coolest portions of the rolled metal undue stresses are produced in rolling. Heretofore annealing or reheating was necessary to give the best structure tc the metal. The approximate power required for rolling is inversely proportional to the fourth power of the temperature of the metal which is being rolled and the stresses set up in the rolls are greatly increased by lowering the temperature of the metal. Breakage of rolls and couplings is commonly caused by rolling the metal too cold and the wear on the rolls is increased when colder metal is encountered. When the metal is uniformly heated to high temperatures, greater reductions in size can be made for each pass through the rolls and for a given amount of power which is applied to the rolls.

One of the objects of the invention is to provide means for maintaining the metal uniformly at high temperatures during rolling without passing the metal through reheating furnaces between rolling operations.

Another object of the invention is to provide means for rolling metals to small sizes and to maintain the metal uniformly at high temperatures during the rolling.

Another object of the invention is to provide .successive roll stands and the pit is lined with means for retaining the metal at uniform and high temperatures while it is being passed through the rolls so that large reductions in thickness can be made in each pass through the rolls.

Another object of the invention is to provide a roll table which is constructed in units so that it can be conveniently assembled and worn parts of the table can be replaced without reconstructing its units.

Other objects of the invention will appear in connection with the description of the drawings which constitute a part hereof, in which:

Figure 1 is a side elevational View of one section of a roll table with parts broken away.

Fig. 2 is a cross sectional view of the table taken along the line 2-2 of Fig. 1.

Fig. 3 is a cross sectional view of the table taken along the line 3`3 of Fig. 1.

Fig. 4 is a partial cross sectional view similar to Fig. 3 in which a modification of the structure .is shown.

rolls is mounted over a pit 15 in the foundation 13. The pit 15 and roll table 14 extend between y heat insulating lining 16. In Figure 1, a section of a continuous mill is illustrated but it is to be understood that the invention is applicable either to mills in which the metal is continuously passed through the successive sets of rolls or to mills f9.5

`in which the metal is passed through the rolls and returned through the same or other sets of Y rolls in the same roll stand.

The conveyors comprise live rolls 17 which are mounted on hollow Vshafts 18 which shafts are 1.00 journaled at their ends in bearings 19. The bearings are' provided with caps 20 which can be removed for mounting the rollers. The base members 21 of the bearings are bolted to the base plates 22 on the foundation 13. VThe live rolls 1.05 17 may be positively propelled through the shaft -23 which extends along one side of the table at the ends of the rolls but other means oi' driving the live rolls can be used. The shaft 23 is connected to the rolls through the worms 24 E110 rolls.

fturned flanges 44 secured to its ends.

l 26 having internal flanges 27 adjacent its ends,

and bushings 28 secured by screws 29 to said flanges 27v to form end walls of the rolls, The bushings 28 are mounted on the shaft 18 and caused to rotate therewith by keys 30. Heat insulating packing 31 may be provided between the f cylinder and the bushings to minimize the conduction of heat from the roll 17 to the shaft 18. The shaft 18 is provided at one-end with an axial inlet duct 32 in communication with the interior of the roll through ports 33 Yin the shaft, while the other end of the shaft is provided with an outlet duct 34 in communication. with the interior of the roll through ports 35 in the shaft. A pipe 36 to supply cooling fluid such as air, steam or Water is connected to the inlet duct 32. A discharge pipe 37 leads from the loutlet duct 34.

Connections between the

pipes

36 and 37 and the ends of the shaft 18 may be made by any of the well known types of unions which will permit the

pipes

36 and 37 to be held stationary and the 'shaft 18 to be rotated. When it is desired to prevent overheating of the rolls 17 and to regulate the temperature of the rolls below that to which they become heated by the metal which is being rolled, cooling fluid is introduced into the interior of the roll through the pipe 36, duct 32 and ports 33. The cooling fluid is discharged from the roll through the ports 35, duct 34 and pipe 37. However, it is to be understood that the rolls can be run without the cooling iluid if it is desired that the rolls shall be maintained at a high temperature.

Side walls 38 extend along the ends of the live rolls 17 and a curved top 39 is disposed on the side walls to form therewith a hood over the The sides of the hood comprise sections of metal channeled members 40 which are bolted to the base members 22 and through which the ends of the rolls 17 extend. Collars 41 are secured in openings in the channeled side members 40 and closely encircle the ends of the rolls 17 to prevent escape of heated air from theV hood. The projection of the rolls through the side members effectively protects the shaft 18 from direct heat. By exposing the outer ends of rolls 17 to the atmosphere, it has been found that the temperature of the greater but less highly heated mass of metal at the ends of the rolls is surprisingly uniform and expansion and contraction of the end metal over short intervals is avoided. The channel members 40 are preferably short so that they can be conveniently lifted from their foundation and removed with the rolls when the rolls are replaced.

The roof 39 of the hood comprises curved metal `sections 42 each of which has longitudinal T- members 43 secured to its outer edges to form a wide bearing surface; Each section 42 has up- The sides and roof of the hood may consist entirely of metal, but for reducing radiation losses to the lowest values, the side walls and roof may be Vlined with heat insulating material 45 such as asbestos, fire brick or concrete. The curved roof causes a maximum amount of heat to be reflected back on the metal.

The insulating lining 45 in the arched hood is retained at the sides by the inwardly projecting flange ofthe T-members 43. The insulation 45 on the side walls of the hood is supported at the top and bottom by angle irons 46 which are attached to the side members 40. The insulation is supported around the rolls 17 and spaced therefrom by the metal guards or collars 4l on the side members 40. The insulation may be reinforced by means of suitable anchoring members such as pins 47 which are attached to the arched roof plate 42 and to the side members 40.

Skid plates 48 are positioned between the live rolls 17 and are supported on the bracket members 49 secured to the sides 38 of the hood by bolts 50. The skid plates 48 are cast or rolled metal members having up-struck ribs or skid members 51 extending longitudinally of the roll table. The spaces or grooves between the ribs 5l are filled with heat insulating material 52, such as sand, mill scale, asbestos, or a suitable strongly adhesive heat insulating material. The insulation on the skid plates is desirable as it materially checks the flow of heat from the upper enclosure of the hood but the insulation may be omitted. The ribs 51 extend upwardly through the insulating material to provide skid members upon which to slide the ingots or shapes, and to prevent the ingots or shapesas they slide along the ribs 51 from contacting with the insulation 52. The insulation may occupy the greater part of the upper surface of the skid plates to give the most effective heat insulating properties to the plates, but the amount of heat insulation effected by the skid plates 48 and the ease of skidding the metal over the plates may be Varied by making the ribs 51 narrower or broader as the case may be.V

The skid plates 48 may be reinforced by spaced webs 53 which extend across the plates on the underside. The ends of the webs terminate in longitudinal ribs 54 on the lower surfaces of the skid plates which ribs serve to align and position the plates 48 between the brackets 49. The skid plates 48 are held from endwise movement by pins 55 which are passed through openings in the skid plate and the bracket 49.

When the metal is passed over the skid plates it sometimes travels to one side so that guards are necessary for keeping the metal in alignment and guiding it along the table, for protecting the sides of the hood, and to prevent the metal from bers consist of high side ribs 56 and extend the Ventire length of the plate 48. According to the modification shown in Fig. 4, the guard consists of angle bars 57 which are attached to the side walls 38 by bolts 58 and which extend therealong contiguous to the skid plates 48. The lower inwardly extending arms 59 of the angle bars 57 function as a bracket to support the plates 48. As shown in Fig. 5, the guard plates 60 are supported by the side wall 38 and are secured thereto by bolts 61.

It is'apparent from the foregoing description that the roll table is constructed in sectional members and that the members are so constructed that they can be assembled and reassembled for replacing the rolls 17 or the skid plates 48 without tearing down the various members of the hood. We prefer to make the hood members in comparatively short sections, say about five to six feet long so that they can be removed, for example, by a crane. The various sections of the hood are held together in endwise relationship to prevent losses of heat by radiation and by convection currents of air.

` Y The sections may be securedl .together by means of U-shaped clamping members 62 which are adapted to straddle the contiguous end flanges 44.

The side members and the roof of the hood are constructed separately, the sides 38 being assembled with the brackets 40 and the insulating lining 45 and the roof 39 being assembled with the sections 42 and their insulating linings 45. In assembling the roll table, a right and left side member are assembled on a roll 17 and the three members are placed in proper relationship on the foundation 13 with the shaft 18 properly aligned in the bearings 19, the side members being arranged on the base 22 of the foundation 13 so as to give uniform clearance between the roll 17 and the collars 41 of the side members 40. The side members 40 are then bolted to the base plate 22 by drawing down the nuts 63 on the bolts 64. In this manner, a battery of rolls and side members associated with the roll stands may be assembled, the side members of the hood being proportioned so that the joints between the sections shall fall between successive rolls. The skid plates are then assembled on the brackets 49 so as to give proper clearances between the ends of the skid plates and the rolls. The top sections 39 of the hood are then lifted by the rings 65 and placed on the side members 38 with the ends of the top sections abutting each other. Finally the clamping members 62 are placed over the abutting flanges 44 of the top sections. The top members 39 of the hood may be secured to the side members 38 by means of bolts 66 which are passed through the outer flanges of the contacting

members

43 and 40.

Reference has been made to a construction in which the heat insulating lining of the hood may be dispensed with. In constructing the hood without a lining in accordance with our invention, it is to be understood that the brackets 49 and the guard members 57 and 60 may be secured directly to the side beams 40 without any intervening material such as the insulation.

With this modiiication, it is possible to make a somewhat narrower hood and to use somewhat shorter rolls, but where it may be desired, the insulation can be removed from the lined hood and suitable spacers used between the beams 40 and the bracket members 67 and the guards 57 and 60.

We claim:

1. A roll table which comprises a series of spaced chambered rolls, driven shafts for turning the rolls, means closing the ends of the rolls and forming a connection between the shaft and the roll, heat retaining walls forming an enclosure around the rolls, and means in the walls to protect the shaft and connecting means from direct contact with heated gases.

2. A roll table which comprises a series of spaced chambered rolls, driven shafts for turning the rolls, means closing the ends of the rolls and forming a connection between the shaft and the roll, and heat retaining walls forming an enclosure around the rolls, said heat retaining walls comprising side walls overlapping the ends of the rolls and shielding the shaft and connecting means from heated gases in the enclosure.

3. A roll table which comprises a series of chambered spaced rolls, driven shafts for driving the rolls, walls forming an enclosure above and below the rolls, flanged end members on the rolls, recessed flanges on the shafts adapted and arranged to carry heat insulating material between adjacent surfaces of the nanges, and means in the hood to prevent direct contact of gases in the hood with the shafts and the flanged ends.

4. A roll table which comprises a series of spaced chambered rolls, skid plates spaced between the rolls, heat retaining walls forming an enclosure above and below the rolls and skid plates, the side walls of said enclosure having openings through which the rolls extend, means at the sides and spaced from the walls to rotatably mount the rolls, supports on said side walls to support and mount the skid plates, the space below said skid plates forming an enclosure for retaining heat below said skid plates, and means to circulate a cooling medium through said rolls to cool the same.

HAROLD ETHERINGTON. KARL HERMANN MOLL.